Lines Matching +full:scan +full:- +full:delay
8 KSM is a memory-saving de-duplication feature, enabled by CONFIG_KSM=y,
19 content which can be replaced by a single write-protected page (which
47 may suddenly require more memory than is available - possibly failing
48 with EAGAIN, but more probably arousing the Out-Of-Memory killer.
60 will exceed ``vm.max_map_count`` (see Documentation/admin-guide/sysctl/vm.rst).
80 how many pages to scan before ksmd goes to sleep
84 been set to scan-time.
89 how many milliseconds ksmd should sleep before next scan
158 scan. It's a noop if not a single KSM page hit the
162 Historically KSM checked every candidate page for each scan. It did
163 not take into account historic information. When smart scan is
164 enabled, pages that have previously not been de-duplicated get
166 de-duplication has already been tried and failed. By default this
172 supported: none and scan-time. The default is none. By setting
173 ``advisor_mode`` to scan-time, the scan time advisor is enabled.
174 The section about ``advisor`` explains in detail how the scan time
182 specifies the target scan time in seconds to scan all the candidate
187 scan time advisor. The default is 500.
191 scan time advisor. The default is 30000.
242 1) How to determine whether KSM save memory or consume memory in system-wide
245 general_profit =~ ksm_saved_pages * sizeof(page) - (all_rmap_items) *
256 process_profit =~ ksm_saved_pages * sizeof(page) -
266 ``ksm_merging_pages`` means a bad madvise-applied policy, so developers or
269 separately 32B on 32-bit CPU architecture and 64B on 64-bit CPU architecture.
270 so if the ``ksm_rmap_items/ksm_merging_pages`` ratio exceeds 64 on 64-bit CPU
271 or exceeds 128 on 32-bit CPU, then the app's madvise policy should be dropped,
278 KSM might help save memory, it's a tradeoff by may suffering delay on KSM COW
290 cannot do all the locking needed to reconstitute a cross-anon_vma KSM page.
298 sized for the maximum number of candidate pages. The scan time advisor can
302 number of candidate pages to scan. Two advisors are implemented: none and
303 scan-time. With none, no advisor is enabled. The default is none.
305 The scan time advisor changes the ``pages_to_scan`` parameter based on the
306 observed scan times. The possible values for the ``pages_to_scan`` parameter is
309 scan all the KSM candidate pages. The parameter ``advisor_target_scan_time``
310 decides how aggressive the scan time advisor scans candidate pages. Lower
311 values make the scan time advisor to scan more aggressively. This is the most
312 important parameter for the configuration of the scan time advisor.
318 The ``pages_to_scan`` parameter is re-calculated after a scan has been completed.
321 --